1. Field of the Invention
The disclosed embodiments of the present invention relate to clock correction, and more particularly, to a clock correction method utilizing a training sequence used for communication link training to correct a frequency of an output clock of an oscillator, and related method for generating a reference clock, clock correction circuit and circuit for generating a reference clock.
2. Description of the Prior Art
A conventional universal serial bus (USB) 3.0 system has to use an external quartz crystal oscillator to provide precise reference clock, which results in additional costs and spaces. In order to save costs and spaces, the manufacturer integrates an oscillator into a system chip to realize a crystal-less design. However, in a conventional crystal-less USB system, a crystal oscillator integrated in to a system chip cannot provide a precise reference clock due to temperature and process variations. This results in system performance degradation.
Thus, there is a need for a novel clock correction method to correct an output clock of a crystal oscillator integrated into a system chip.